Adjustable strength door latch



April 23, 1963 H. C. WILSON ADJUSTABLE STRENGTH DOOR LATCH Filed July18, 1960 IN V EN TOR. HARRY C. WILSON ATTORNEYS grates finite 3,686,803ADJUSTABLE STRENGTH DGOR LATCH Barry C. Wilson, 15126 Rayneta Drive,Sherman ()aks, Calif. Fiied July 18, 1960, Ser. No. 43,678 1 Uaim. (Cl.292-17) This invention relates to door latches and more particularly toa simple, inexpensive, button-type latch device featuring easilyoperable means by which the holding power of the resilient retainer maybe varied at will over a Wide range.

The door latch of the present invention is commonly known as abutton-type latch inasmuch as one of the two principal componentscomprises a contoured button which resiliently interlocks with theretainer assembly. A variety of designs embodying the operatingprinciples of a button latch have been proposed heretofore. However,they have not been fully satisfactory in certain respects and have notenjoyed widespread use owing to certain shortcomings and disadvantagesincluding the lack of simple, easily operated and reliable means foradjusting the holding strength to meet the needs of differing operatingenvironments or the preferences of a particular user. Also lacking inprior constructions has been a desirable range of adaptability todiffering environments or the change of conditions in a givenenvironment due to shifting of the supporting walls or doors to whichthe latch parts are attached, shrinkage of the wood on which the partsare mounted and numerous other factors of a like character.

The present invention is provided to meet the above discussed and othershortcomings of prior latch devices and to provide a device that can bereadily adjusted after installation to meet changing conditions both asrespects the relative positions of the latch parts and in particular theholding power of the catch itself. To this end the latch comprises acup-shaped retainer having a dished bottom through which the mountingscrew or the like extends. Tightening or loosening of this mountingscrew to change the degree of dish of the retainer bottom is eifectiveto change the normal position of the retainer fingers and thereby theholding power of these fingers relative to the detent button. It willtherefore be appreciated that adjustment is obtained without need forspecial or additional parts and adjustment is accomplished by the aid ofa screwdriver to turn the mounting screw.

A further feature is the use of a detent button formed of non-metallicnoise-absorbing material and mounted on the shank of an attaching screw,The use of a non-metallic button in combination with the spring retainerrenders the catch substantially noiseless in operation and has theadditional advantage that it can be assembled to the mounting screw witha very firm frictional contact. By reason of this latter fact, themounting screw can be adjusted axially thereof over a wide range withassurance that the button proper will remain firmly seated against thehead of the mounting screw. In this manner the proper operatingpositions of the latch components can be maintained and changed asnecessary to compensate for warpage of the door, sagging and the likechanges.

Accordingly, it is a primary object of the present invention to providean improved button-type latch device of simple, inexpensive constructionand embodying highly desirable novel features.

Another object of the invention is the provision of a simple springcatch door latch having improved means for adjusting the holding powerof the latch over a wid range.

Another object of the invention is the provision of an improvedsubstantially noiseless spring detent latch device having severalcooperating adjustable features.

These and other more specific objects will appear upon reading thefollowing specification and claims and upon considering in connectiontherewith the attached drawing to which they relate.

Referring now to the drawing in which a preferred embodiment of theinvention is illustrated:

FIGURE 1 is a fragmentary view in perspective showing a latch deviceaccording to this invention in operating position on a cupboard door;

FIGURE 2 is an enlarged cross-sectional view through the latch device inthe closed position thereof;

FIGURE 3 is a cross-sectional view taken generally along the line 33 onFIGURE 2; and

FIGURE 4 is a view similar to FIGURE 2 but showing the retainer assemblyadjusted for relatively low-power holding capability.

Referring to FIGURES 3 and 4, there is shown a button-type latch devicedesignated generally 10 formed in two assemblies comprising a retainerassembly 11 and a detent assembly 12. As herein shown, retainer assembly11 is shown secured to a cupboard shelf 13 by mounting screw 14 anddetent assembly 12 is shown mounted on the interior side of a cupboarddoor 15 opposite assembly 1 1. It will be, of course, apparent that thetwo principal subassem'blies can be mounted in various other modes wellknown to those familiar with the latch art and the numerous modes ofusing such devices.

The principal parts of retainer assembly 11 comprise a one-piececup-shaped member formed from resilient sheet material and having aninwardly dished bottom 17 and a plurality of spring fingers 18 arrangedgenerally parallel with one another and spaced circum-ferentially of andintegral with the rim of bottom 17. The free ends '19 of fingers 13 arepreferably similarly curled, either inwardly or outwardly, and arearranged in a ring in the manner clearly illustrated in the severalfigures of the drawing.

Dished bottom 17 of the retainer is suitably apertured to receive theshank of a mounting screw 20. As herein shown the shank of this screw isengageable with a threaded opening 21 in the upright leg 22 of anL-shaped bracket member 23. The other leg 24 of the bracket has anopening 25 for receiving the shank of mounting screw 14. A further andimportant feature of the mounting bracket 23 is the provision of apointed tang 26 extending generally perpendicularly from the rear faceof leg 24. This tang is forced into the shelf 13 as the mounting screw14 is tightened and cooperates with this screw in determining theorientation of the axis of retainer cup 18 in the installed position ofretainer assembly 11. It is, of course, desirable that the axis of cup18 and of screw 29 be in axial alignment with the axis of detentassembly 12. Once this position has been determined, anchor tang 26 ispressed into shelf 13 and. screw 14 and firmly tightened to lockretainer assembly 11 in this desired position.

Detent assembly 12 comprises a mounting screw 30 and a non-metallicdetent button or ring 31; Button 31 is provided with a central axialopening of the diameter snugly fitting the slightly larger diameterinner end of the shank of screw 30. This fact together with the actionof the screw threads in cutting a helical groove in the button assuresthat this button will have a very tight fit with the screw shank once itis fully assembled against the head of the screw. The exterior peripheryof button 31 is provided with a detent groove 32 the inner rim edge ofwhich merges with the 'base of a flange 33 and the exterior rim of whichmerges with a surface 34 which is suitably contoured to mate with therounded head of screw 30.

The assembly of the parts is accomplished by first mounting the retainerassembly utilizing screw -14 for this purpose. This screw is driven intoa shelf or a wall after first checking to determine that the curled freeend 19 of the retainer member is spaced inwardly of the inner surface ofthe closure when closed. Once retainer assembly 11 has been secured inplace, detent assembly 12 is inserted within the retainer leaving thepointed end of mounting screw 30 projecting forwardly. 'While the detentis so firmly held, the cupboard door 13 is closed against the pointedend of the screw to mark the place where the screw should be mounted.Marking of the mounting place having been accomplished, screw 30 ismounted in the door and checked for proper assembly. Desirably the partsare so mounted that in the installed position of the detent the base endof button 3-1 bears against the inner surface of door 15 and will thenbe properly positioned for the curled ends 19 of the retainer fingers toseat snugly within groove 32 of button 31.

After installation, it sometimes happens that the wood or shelf 13shrinks. In this event the fingers will no longer have suflicientseating engagement with groove =32 to hold the door firmly closed. Tocorrect for this change in conditions, the user merely inserts ascrewdriver in the head ofrscrew 30 and turns it outwardly suflicientlyfor proper engagement of the latch parts. The presence of a narrow gapbetween the inner flanged end of ring 31 and the door is notobjectionable.

Even with the parts properly adjusted for full seating of curled ends 19of the fingers in retainer groove 32, the cupboard door may besutficiently heavy that greater power of the latch parts is desirable.This requirement is easily and readily achieved by the simple expedientof using a screwdriver to turn retainer mounting screw inwardly therebyflattening somewhat the dish in bottom =17. When the dished bottom ispartially flattened in this manner, it willbe understood that fingers 18are deflected inwardly toward the axis of the cup and into firmerseating engagement with groove 32 of button 31. On the other hand,loosening of mounting screw 20 allows the dished bottom to move backtoward its original and normal contour thereby moving fingers 18 awayfrom the axis of the cup and out of strong engaging power with groove 32of the button.

It is found that a retainer formed of light gauge strong spring metalhaving a bottom dishedinwardly by an "angle of 15 degrees is readilyadjustable to vary the retaining power of the catch over a range of 3 to14 pounds. Stated differently, the retainer is adjustable to provide aholding power from a minimum value of say 3 pounds to a maximum of morethan four times the minimum. A greater range of adjustment is readilyavailable by the proper selection of materials andv the use of a dishedbottom having a greater angle of initial dish. Although spring metal isa preferred material from which to construct the retainer, it will beobvious that high-strength,

high res'iliency, non-metallic materials, such as plastic, maybeemployed if desired.

While the particular adjustable strength door latch herein shown anddisclosed in detail is fully capable of attaining the objects andproviding the advantages hereinbefore stated, it is to be understoodthat it is merely illustrative of the presently preferred embodiments ofthe invention and that no limitations are intended to the details ofconstruction or design herein shown other than as defined in theappended claim.

I claim:

A latch device for use in holding a swinging closure member releasablyin closed position, and comprising as principal components a detent unitand a keeper unit, said keeper unit .comprising a cup-shaped resilientmember formed from resilient sheet metal stock, said cupshaped memberhaving a multiplicity of long narrow fingers of flat uniform thicknessmaterial integral with an inwardly-dished centrally-apertured bottom ofsaid member, said fingers being arranged in a ring about the rim ofsaiddished bottom and each having similar inwardly-curled ends forming aring of similarly-shaped similarly-disposed curls about the rim of saidcup-shaped member and cooperating to provide an annular resilient piloteffective to 'guide the detent unit into holding engagement with thecurled ends of each of said fingers, screw means receivable in theaperture of said inwardlydished bottom and eflective to mount saidkeeper memher, said screw means being adjustable to vary the curvatureof saidinwardly dished bottom as and to the extent desired thereby todeflect said ring of fingers radially inwardly and outwardly to vary thecircumference'of said ring of curls and to vary the holding powerthereof, said detent means including a headed wood screw and anannularly grooved ring of plastic material surrounding the shank thereofand positioned adjacent the screw head and shaped to enter said keeperwith the curled ends of said fingers seated in said annular groove, saidplastic ring having a rounded rim edge merging with the exterior endsurface of said wood screw and serving as a rounded pilot engageablewith the curled ends of the keeper fingers to guide the sameindividually and noiselessly into and out of holding engagement withsaid keeper member, and said plastic ring having tight frictionalengagement with the shank of said wood screw References Cited in thefile of this patent UNITED STATES PATENTS 444,019 Richards Jan. 6, 1891504,142 Wilburn Aug. 29, 1893 548,501 Barbarow Oct. 22, 1895 1,931,695Hall Oct. 24, 1933 2,203,973 Walls June 11, 1940 2,694,592 Borchers eta1 Nov. 16, 1954 2,877,040 Curtiss et al Mar. 10, 1959

